Construction of a finite element model of normal human foot and ankle

Abstract

Objective To report the construction of a finite element (FE) model of normal human foot and ankle which can be used for biomechanical research. Methods Helical CT scan images of a 30-year-old male volunteer's right foot were obtained, The 3D structures of 28 bones and surrounding soft tissues of the foot and ankle were reconstructed with Mimics software. After processed by SolidWorks, the Workebench modules of Ansys were imported to establish a meshed accurate geometrical model of the foot and ankle. The articular cartilages, ligaments, plantar fascias, crural interosseous membranes were also simulated in the model according to anatomic and literature data. The normal standing status of the ankle joint was simulated for loading analysis using appropriate boundary conditions. Results The 3D FE model of normal human right foot complex, including bones and surrounding soft tissues, represented the basic anatomic structures and mechanical properties of the human foot and ankle. When a vertical load of 600 N was added on the upper section of the lower tibia at the simulated standing status of the ankle, the stresses on the ankle joint articular surface of the tibia was mainly distributed at the central and anterolateral aspects, with the maximum stress of 3.97 MPa, average contact stress of 1.52 MPa and contact area of 343.6 mm~2. Conclusion The 3D FE foot and ankle model can be constructed and reliably used in the study of foot and ankle injuries. Key words: Foot; Ankle; Finite element analysis; Biomechanics; Digital technology